Switch



Sept. 20, 1932. c. CHRISTENSEN SWITCH- Filed March 12. 1928 2 Sheets-Sheet 1 I My Sept. 20, 1932.

.. c. CHRISTENSEN SWITCH Filed March 12, 1928 2 Sheets-Sheet 2 WWW w W l Ha .5 M. (W/

Patented Sept. 2%, 1932 warren srras Pic-E ,CHRISTEN CHRISTENSEN, OF HAYWOOD, ILLINOIS ASSIGNOR,TO ELECTRICAL, ENGL. NEERS EQUIPMENT 80., OF MELROSE EAR-K, ILLINOIS, A CGRPQR-ATIQN' OF ILLINOIS sol swrrcrr Application filed March 12, 1928. Serial No. 260,848.

This application is a continuation in part of my copending application Serial No. 656,442, filed August 8, 1923, and issued July 16, 1929 as Patent No. 1,720,818.

My invention relates to electric'switches, and more particularly of the disconnect type such as are adapted for disconnecting Oll switches or other pieces oii'apparatus and the like. V

Disconnect switches are required to carry the full loadcurrent of the apparatus or conductors to which they are attached, and should oiier as low a resistance as is possible, in order to avoid electrical losses and to avoid K heating. At the sametime, they must remain closed underconditions of short circuit where a large flow of current is to be conduct-ed. Such overloads as are occasioned by short circuits and the like have a tendency to blow a disconnect switch open, and it has become necessary in circuitsoi any capacity to pro- 'videmeans for locking the blade or the switch in closed position.

On switches employed on cn'cults of coniderable voltage, the supporting insulators for the switch parts must be increased in length between the live parts and the grounded frame, and, at the same time, the length of the blade must be increased to provide a greater gap or striking space when the switch is open. On such voltages and under such conditions the stresses which are encountered have a considerable leverage on the ends of the insulators and tend to spread the insulators, and accurate spacing of the contacts of the switch cannot always be maintained. Likewise, the tension of connected conductors sometimes imposes a strain on the insulators, with the result that the maintenance of any precise distance between the contacts is not commercially feasible. Likewise, the contraction and expansion of the partsrmay cause a variation between the contacts as may the natural. inaccuracies of manufacture.

It is therefore desirable to provide locking means which is not dependent upon enact and accurate spacing being maintained be tween the hinge contact and the free contact of a switch of this character, and which may be used on'double throw switches as well as single throw switches.

The preferred embodiment of my invention, as herein disclosed and illustrated, is, a double blade switch, but I wish to point out that the invention is not to be limited to-a double bladeswitch, as will more fully here-V inatter appear. I V j if here a double blade switch is employed, the problem of locking both of the blades-and simultaneously releasing them, presents a difficulty which must be overcome.

The lock part must be rugged and capable of withstanding the. rigors of service and of weather conditions without failure.

Where a relatively long switch arm is-enia ployed, difliculty is sometimes encountered in guiding thearm into engagement with the free contacts and I have provided in the preferred embodiment of my invention combined locking and guiding means which serve efficiently to guide the arm intoengagement with the contacts and,at the same time, to per.- form the service of locking the arm in such position.

My invention may be applied to single throw or double throw switches with equal facility. Y

Simplicity of construction and ease of con struction and manipulation are highly desir-' able as also is low cost of construction, and all these qualities are embodied in the switch of my invention.

Now, in order to acquaint those skilled i the art with the manner of constructing and operating a device embodying my invention, I shall describe in connection with the ac-' companying drawings a specific embodiment of the invention.

In the drawings Fig. 1 is a side elevational embodying my invention;

Fig. 2 is a top plan view of the same;

Fig. 3 is a top plan view of a modification;

Fig. 4 is a sectional view on an enlarged scale taken on line 44 of Fig. 2; and i Fig. 5 is a plan view of the hinge plates mounted on the base of the front contact.

The hinge contact 1, to which the switch arm 2 is hinged, is mountedupon an insulator lGO 3 which may be of any suitable or preferred construction, this insulator being in turn mounted upon a rigid base also supporting the insulator 4 upon which the free contact 5 is supported. The hinge contact 1 is provided with a suitable base 6 preferably integral therewith which is connected to the top of the insulator 3 by means of the cap screws 7. The base 6 has a terminal lug 8 integral therewith. The two sides of the contact stud 1 are milled or otherwise machined to have parallel faces, and the switch arm 2, consisting of the two blades 9 and 10, is pivoted to said pivot contact stud 1. The blades 9 and 10 are applied to opposite sides of the contact 1 and a hinge bolt 11 forms the pivot. This hinge bolt draws the spring washers 1213 against the outsides of the blades 9 and 10, and the pressure which these spring washers apply to the blades and, hence, the blades to the sides of the contact 1, may be adjusted by the bolt 11. although this is generally suitably adjusted at the factory and the end of the bolt spun or riveted over so as to prevent accidental unthreading of the nut from the bolt or any release of the tension upon the spring washers. I

The free or front contact stud 5, l kewise. has an integral base 15 secured to the cap of the insulator 1 by the bolts 16 which also pass through holes in the hinge brackets or plates 50-50-. A terminal lug 17 which may be integral with the base 15, provides a suitable line connection to the stud 5.

The sides of the free contact stud 5 are carefully machined to be substantially parallel like the contact stud 1, and it is preferable that the thickness of the two contact studs 1 and 5 be substantially the same. Minor variations in thickness between these two studs is permissible and, in fact, as the switch wears in use the front contact stud 5 generally wears away to a greater degree than the hinge contact stud. By the provision of su table spring loading means, such vwear or such differences in thickness or exact alignment is taken up. This spring loading means comprises the pairs of spring washers 19 and 20 upon opposite sides of the contact stud 5. That is to say, the spring washers 1919 l e upon the outsides of blades 9 and 10 in front of the front contact stud 5, .and the spring washers 20 lie upon the outsides of blades 9 and 10 to the rear of the front contactstud 5.

Tensioning bolts 21 and 22 pass through said pairs of washers and their engaged blades and apply a suitable spring pressure to the outsides of the blades to press the blades against the sides of the front contact stud 5 with sufficient firmness to take up the wear wh ch the switch encounters and to make up for such inaccuracies of manufacture as may be encountered.

The bolts 21 and 22 pass loosely through the blades 9 and 10 so as not to obstruct play in and out of these parts in securing good contact with the front stud 5.

Obviously, instead of using pairs of spring washers upon opposite sides of the front contact stud, a single spring on each side may be employed, the ends thereof being held under the heads of the bolts 21 and 22, the central part of such spring bowing inwardly towards the contact and applying pressure to the blades 9 and 10 over the area where such blades overlap the contact stud 5.

The forward ends of the blades may be free to play towards and away from each other, but this is not essential since sufficient flexibility may be inherent in the blades to secure the desired pressure of the blades against the contact stud 5 independent of the remote parts of the blades. That is to say, it will be apparent that the relatively long extent of the blades between the front contact 5 and the hinge contact 1 is sufficiently yielding, so that even if the hinge contact 1 should be considerably thicker than the front contact 5, the rigid, or relatively rigid, holding of the blades against the sides of the hinge contact 1 would not interfere with securing the proper pressure of the blades upon opposite sides of the front contact stud 5, or the inward motion of such blades to take up the wear on the front contact 5, or to take up such inaccuracies in manufacture as I encountered on reasonably accurate work.

The same is true at the front end. If the point of attachment is so remote as to permit sufficient freedom of motion of the blades .at contact 5 the requirement for floating action contemplated within this form of service is satisfied. 7

Thus, it will be apparent that whether the extreme front ends of the two blades 9 and 10 are held a fixed distance apart or are allowed to move is immaterial within my invention.

I have shown the front ends of the blades as being spaced apart by a collar 24 mounted on a pin25, which pin serves as a pivot for the unlocking member 26.

The unlocking member 26 serves not only as an unlocking member, but also as an operating member for the switch arm. The unlocking member 26 has, at its extreme front end, an operating ring or eye 27 adapted to receive an operating hook such as is in common use, namely, ametal hook or pin fastened on the end of a pole of insulating material whereby the operator may open or close the switch without danger of contact with the live parts.

The body of the unlocking member 26 is bifurcated comprising the parallel portions 28-28 lying upon the outsides of the ends of the blades 9 and 10. The pivot pin 25 passes through said parallel portions 2828 and through the blades 9 and 10. The pin 25 is held in place by connecting the same to the locking shoulders, 33-33 forming detents for restraining the blades 9 and 10 from moving upwardly. The blades 9 and 10 are prevented from movingdownward on the frontcontact stud 5 by a shoulder 32 on each side,

and are prevented from moving upwardly by the shoulders or hooks 33-33 which over hang the upper edges of the blades 9 and 10,

as is apparent from Fig. 4.

The members 30-30 are provided with spaced hinge lugs 34-34 between which are disposed hinge lugs or brackets 35-35 inte gral with the base member of the frontcontact stud 5. A hinge pin 36 is passed through the lugs 34-34 and 35-35 to permit the members -30 to swing in a plane transverse to the longitudinal axis of the switch arm. The end of the pins 36 are riveted. A coiled spring 37 is coiled about the hinge pin 36 between the stationary lugs -35 and one end of, the spring bears against the base 15 and the other end of the spring bears against themember 30, tending to throw it, in each case, toward the free contact stud 5. w

While in Fig. 4 the members'30-30 are shown as being disposed exactly vertical and having their inner sides in flat contact with the sides of blades 9' and 10, in practice I prefer to have the members 30-30 tilt inwardly slightly so that the lower inner corners 51-51 form stops against base 15 for the members 30-30 when the blades 9 and 10 are swung open. Likewise the shoulders or projections 52-52 are adapted to form stops limiting the outward swinging-motion of members 30-30. g

It can thus be seen that, if the switch is open, the operator may, with a suitable hooked stick, hookinto the eye 27, close the switch, the bladebeing guided by the horn or guiding surfaces 31-31 down onto the front contact stud 5, and the arm may be pushed down to the point where the blades are stopped against the shoulders 32, and slightly before the blades are stopped on the shoulders 32 the hooks or shoulders 33 on the members 30 drop over the upper edges of the blades9 and 10 to lock the blades against opening.

The releasin and operating member 26 V has fingers 38 extending towards the members 30, and the members 30 have downwardly andinwardly' sloping cam surfaces53-53' provided on the inside of the. integrallugs 39-39 adapted to be engaged by said fingers or studs 38 on the operating and releasing member 26 so that, as the operator pulls on the eye member 27 in a direction to open the switch, the pins or studs 38 bearing against the cam surfaces 53-53 cause the members 30-30 to be swung outwardly about their hinge pins 36 sufliciently far to release the hooks or shoulders 33-33 from the blades 9 and 10, whereupon, continued pulling on the rlng or eye 27 moves the blades freely from a position where they can again be seized b the hooks 33-33 as the fingers or studs 38 move upwardly with the'blades 9 and 10.

The pivotal motion of the releasing member 26 about the ends of the switch arm, that is, the blades 9 and 10, may be limited, by the formation of the ends of the blades 9 and 10, but I prefer to limit the motion by overhanging webs or flanges 40-40 which engage the heads of'the front bolt 21. In this man nor, the downward motion of the pins or studs 38-38 is limited to an extent which is sufiicient to release the members 30-30 from locking the blades 9 and 10. until the blades emerge sufiiciently from contactwith the front contact stud 5 to prevent the hooks or shoulders 33-33 from again catching the upper edges of the blades 9 and 10 as the switch is opened.

Preferably, flanges 41-41 on the bottom side, like the flanges 40-40, limit the angular motion of the releasing member 26 in the opposite direction. That is to say, when the switch is closed, the operator presses down wardly on the ring 27, as viewed in'Fig. 1, and the angular motion of the releasing member 26 is limited by the flanges 41 engaging the head of the bolt 21, or, as above explained, any other suitable stop of this releasing member with respect to the blades may be promay travel inward as wear occurs on the con-' tact 5. This, however, as aboveexplained, is not necessary where the location of the spacing collar 24 is sufficiently remote from the part of the blade which engages the stud 5 to give the spring means sufficient freedom of action to apply the blade to the contact stud.

In Fig. 3, I have shown a modified form in which the switch arm 42 comprises a single blade adapted to cooperate with the split front contact 43. This split contact is mounted upon a suitable base 44 and upon the same base the members 45-45, corresponding in all respects to the members 0-30, are pivotally mounted provid d ing surfaces 3131.

with springs tending to cause the shoulders 8383 thereof to overhang the edge of the single blade 42 to lock the blade in closed position.

The releasing member 46 is provided with an operating eye 27, identical with the operating eye shown in Figs. 1 and 2, and the studs or fingers 4747 engage cam surfaces provided by the lugs 394-391 just as in Figs. 1 and 2. I 1

In the present case, the angular motion of the releasing member 46 is stopped by the square end of the blade 42 against which the member 46 swings to limit its angular motion. lhe latching and unlatching of the single blade 42 by the members 45 and 46 is the same as that described in connection with Figs. 1 and 2.

It is to be observed that the movement of the studs 38, as shown in Figs. 1 and 2, and the studs 47, as shown in Fig. 3, is such as not to interfere with the members 30-30 or the members 4545 as the switch arm is opened or closed. 1 7

By employing separate cam surfaces and contacting fingers on the releasing member 26, no undue wear is placed upon the shoulders 3383 as is the case in certain devices heretofore in use, where the spreading of the detents, such as 3080, has been accom plished by means wedging between the guid- The constructions herein shown provide a highly satisfactory form of locking mechanism which is particularly applicable for outdoor service.

Preferably, the inner surfaces of the arms 2828 are milled to provide a close fit with the outsides of the ends of the blades 9 and 10 so that rattle or looseness of the parts is minimized.

I do not intend to be limited to the details shown or described.

I claim a 1. In combination, a switch contact, apivoted switch blade cooperating therewith, a detent resiliently pressed towards the blade and adapted to hook thereover, the portion of the blade engaging the Contact being 10- cated between the detent and the contact them into firmer engagement, and adapted to hook over the blade, and a bifurcated releasing member for the detents pivoted on the end of the blade and embracing the end there- 7 of and having portionslying along the side of the blade and extendinginto engagement with the detents for releasing'the same.

3. In combination, a switch stud, a switch arm comprising a pair of blades adapted to embrace said stud, a pair of pivoted detents lying outside said stud and having guiding surfaces to guide the arm between them over the stud, said detents having shoulders adapted to hook over the edges of the blades and having cam surfaces between the shoulders and the pivots, a bifurcated release member embracing the ends of the blades and pivoted thereupon, said. member having projecting fingers cooperating with the cam surfaces upon pivotal motion of the release member to disengage said shoulders from the blades.

4. In combination, a switch stud, a switch member, the ends of the blade, and through T the spacing means to provide a pivot for the releasing member, said releasing member having an eye extending beyond the end of the switch arm, the two limbs of the bifur-, cated member lying alongside the blades and adapted toengage the detent members along an edge extending lengthwiseof the blade for releasing the detent members.

5. In combination, a pair of switch studs, a switch arm comprising a pair of blades pivoted on one stud and adapted to embrace the other stud, hooked detents pivoted adjacent the said second stud, and a releasing member embracingthe ends of the blades and pivoted thereto, means for holding the ends of the blades together, said means limiting the angular movement of the releasing member, and cooperating cam means on the releasing member and on the detent members for releasing the blades from the detent members when a pull is exerted upon the end of the release member in the direction to open the switch.

the hinge stud, spacing means between the outer ends of the blades, spring means for pressingthe blades against the sides of the free stud when the switch is in closed position, a pair of hooked detent members pivotally mounted adjacent the free contact stud, a swinging release member pivoted on the end of the blades and having an eye eX- tending beyond the ends of the blades, said release member having portionsextending along the sides of the blades outside of said spring means and cooperating with the detent means upon the pull on the operating eye for first swinging the detent means about their pivots to release the blades and then to move the blades away from the free contact stud, said spring means limiting the ex- 'lIO tentof pivotal movement of the release memher 7 In combination, with suitable insulating means, of a pair of contact studs, a pair of blades hinged on one of the contact studs and adapted to cooperate with the free contact stud, a pair of spring pressed detent members adapted to hook over the blades when the switch is in closed position, spring means on the blades outside of the free contact stud for limiting the extent of spreading of the blades, a releasing member embracing the ends of the blades and pivoted thereto intermediate. its length, said releasing member having a pulling eye and having portions extending along the sides of the blades into cooperating engagement with the detent members for releasing the same, said portions extending outside ofsaid spring means and having shoulders adapted to engage with said spring means for limiting the angular motion of said releasing member.

8. In combination, a pair of switch contacts comprising a hinge contact and a free contact, a switch arm for connecting said contacts hinged on the hinge contact, a

hooked detent mounted at the side of the free contact adapted to spring over the up-v per edge of the switch arm at the portion of the switch arm adjacent the tree contact when the switchis in closed position, said detent urging the switch arm toward the contact, and a pivotal releasing member mountedon the end of the switch arm and having a portion cooperating with the detent independently of the hook portion thereof 'for releasing the arm from the detent.

- 9. In combination, a pair of switch contacts comprising a'hinge contact and a free contact, a" switch arm hinged to thehinge contact and adapted to cooperate with the freecontact, a pair of detent members having guiding arcing horns for guiding the arm into engagement with the free contact and for preventing arcing between the arm and the contact, said horns having shoulders adapted to hook over the arm, said detent members being resiliently pressed towards the blade to cause the shoulders on the detent members to drop over the arm and to bring the arm and the free contact into :firmer engagement, and a pivotedreleasing member having limited angular motion on blade against the contact, and cam means carried by the blade and cooperating with the opposite face ofthe locking member for releasing the blade. 7

11. An electric switch including a contact member, a locking member having free movement towards and awaytrom the contact member, a switch blade operating'between blade and cooperating with the opposite face I of the locking member for releasing the blade, said cam means being symmetrical about a longitudinal axis of the switch blade.

12. An electric switch including a pair of spaced supporting insulators, a hinge contact mounted on one of the insulators, a free contact on the other insulator, a blade hinged to the hinge contact and adapted to cooperate with the free contact, a pivoted locking member adjacent the free contact for locking the blade in position, and a lock releasing member extending lengthwise of the blade and pivoted at the end thereof for releasing the locking member, said release member and said lock member engaging one another along a line extending lengthwise of the blade, thereby avoiding interference with the lock by a spreading of the insulators, said lock release member being symmetrical about a longitudinal center line ofthe blade whereby the switch may be made a single throw switch or a double throw switch.

13. An electric switch including a pair of spaced insulators, a switch contact supported on one of the insulators, a cooperating blade mounted on the other insulator, a pivoted locking member adjacent the contact for locking the blade inposition, a releasing member mounted on the blade, said releasing member and said locking member having overlapping 7 may be used one single throw or double throw switch, and means carried by the blade for limiting the extent of movement of the re leasing member in either direction from its normal position.

14:. An electric switch including a pair of spaced insulators, a switch contact supported on one of the insulators, a cooperating blade mounted on the other insulator, a pivoted locking member adjacent the contact for locking the blade in position, and'a releasing" member mounted on the blade, said releasing member and said locking memberhaving overlapping engagement whereby a spreading of the insulator does not interfere with V the action of the releasing member, said releasin member bein substantiall s mmetrical about a longitudinal center line of the blade and movable from its normal position alike in either of two directions whereby the switch blade may be used on a single throw switch or on a double throw switch.

15. A switch having a blade comprising a pair of parallel floating blade members pivotally mounted at one end, bolt means adjacent the opposite end of the blade members for limiting the extent of permissible spreading of that end of the blade members, a lock for the blade, and lock releasing means mounted on the blade adjacent the bolt means, said lock releasing means having movement in two directions with reference to the blade and including means on opposite sides of the axis A of the bolt means movable into engagement with the opposite sides of the bolt means upon a predetermined movement of the locking means in either direction whereby the bolt means limits the movement of the lock releasing means in either direction.

16. An electric switch including a switch blade comprising a pair of floating blade members pivotally mounted adjacent one end,

means including a bolt extending through the blade members adjacent their other end for limiting the extent of spreading of said blade members, locking means for locking the switch blade in the closed position, and lock releasing means mounted on the outer side of the blades, said bolt cooperating with said lock releasing means for limiting the extent of movement of the releasing means with respect to the blade.

17. A switch comprising a hinge contact and a free contact and a blade hinged to the hinge contact and adapted to be swung into engagement with the free contact, a locking detent swingable towards and away from the blade about an axis extending substantially longitudinally of the blade when the same is in the closed position, said detent being yieldingly urged towards the blade and having cam means on the side thereof opposite the side of the detent that is adjacent the switch blade, and releasing means mounted on the blade adjacent the free contact and cooperating with the cam means on the outer side of the detent for releasing the detent, said cam means moving in a plane parallel to the side of the switch blade and spaced therefrom, and movable alike to either side of the longitudinal center line of'the blade. a

18. A switch including a blade, acontact adapted to be engaged and disengaged by the blade, a hooked'locking detent swingable towards and away from the blade about an axis extending substantially longitudinally of the blade when the blade is in the closed position, said detent being yieldingly urged toward the blade whereby when the blade is in the closed position the edge of the detent hooks over the edge ofthe blade to lock the same, and, the inner face of the detent lies substantially parallel to the side of the plate, cam means on the opposite outer face of the detent, and detent releasing means mounted on the blade and adapted to engage the cam means to move the detent to the blade releasing position.

I 19. A switch including a blade, a contact adapted to be engaged and disengaged by the blade, a hooked locking detent swingable to- 375 wards and away from the blade about an axis extending substantially longitudinally of the blade when the blade is in the closed position, said detent being yieldingly urged toward the blade whereby when the blade is in the closed position the edge of the detent hooks over the edge of the blade to lock the same, and the inner face of the detent lies substantially parallel tothe side of the blade, cam means on the opposite outer face of the detent, and

detent releasing means mounted on the blade and adapted to engage the cam means to move the detent to the blade releasing position, the portions of the releasing means and the cam means that engage one another having a permissible relative movement in a direction lengthwise of the blade without resulting in a disengagement of the two.

20. A switch including a blade, a contact adapted to be engaged and disengaged by the blade, a hooked locking detent swingable towards and away. from the blade about an axis extending substantially longitudinally of the blade when the blade is in the closed position, said detent being yieldingly urged T toward the blade whereby when the blade is in the closed position the edge of' the detent hooks over the edge of the blade to lock the same, and the inner face of the detent lies substantially paralled to the side of the blade, 7105 cam means on'the opposite outer face of the detent, and detent releasing means mounted on the blade and adapted to engage the cam means to move the detent to the blade releasing position, said releasing means comprising a lever pivoted to the blade between the free end of the blade and the contact, and extending along the side of the blade to the cam on the outer side of the detent.

21. A switch including ablade, a contact blade when the blade is in the closed position, 3120 said detent being yieldingly urged toward the blade whereby when the blade is in the closed position the edge of the detent hooks over the edge of the blade to lock the same,

and the inner face of the detent lies substan- 3125 tially parallel to the side of the blade, cam means on the opposite outer face of the detent, and detent releasing means mounted on the blade and adapted to engage the cam means to move the detent to the blade re- 7130 leasing position, said releasing ineans comprising a lever pivoted to the blade between the free end of the blade and the contact,'

and extending along the side of the blade to the cam on the outer side of the detent, the portions of the releasing means and the cam means that engage one another having a permissible relative movement in a direction lengthwise of the blade without resulting in adisengagement of the two.

In witness whereof I'hereunto subscribe my name this 1st day of March, A. D. 1928.

CHRISTEN CHRISTENSEN. 

